Towards the end when alternate Olivia is typing on the typewriter, she clearly presses down on a g. When you see what she has typed, there is no g in the sentence.
Pilots communicate with Air Route Traffic Control Centers in VHF (frequencies from 108 to 137 MHz). HF, as shown in the episode, is used only on remote locations where VHF waves cannot reach, such as in transatlantic routes or the Arctic, for instance.
The Ancient Calendar shows 360 days in the year, millions of years ago there were more days in the year, not less, as days are very slowly getting longer, there will be 360 days in a year around 40 million years in our future.
There's no "Baltimore Center" in the USA, as mentioned by the pilot. In the area (DC/Richmond), an aircraft would most probably be in contact with Washington Center.
Judging from the appearance, the Polish "transistor" Peter pulls from the cube is actually a voltage regulator. Mosfet transistor, Bipolar transistor looks almost the same like voltage regulator.
When Astrid holds up the LP record, its cover clearly says "The Art of the Fugue" by Johann Sebastian Bach; however, when the record is played, what we hear is the "Air" from the Suite No. 3 in D major, BWV 1068, also known as "Air on the G String".
'Landau 287' is a bizjet, but the sound is that of a propeller driven aircraft.